A method, apparatus and device for simulating a far-field wavelet based on a near-field recording

Abstract

The application discloses a method, device and equipment for simulating a far-field wavelet based on near-field records, which can comprise the following steps: determining the distance from a seismic source to a near-field detector and the distance from a virtual seismic source to the near-field detector based on the near-field records of the near-field detector, the moving speed of the near-field detector and the travel time at each sampling moment, so as to construct an ideal wavelet corresponding to each sampling moment; determining the distance from the seismic source to a far-field point and the distance from the virtual seismic source to the far-field point based on the obtained near-field records of the near-field detector; determining the travel time of a far-field wavelet directly below a seismic source array based on the sampling point number corresponding to the travel time and the time direction sampling interval; and simulating and generating the far-field wavelet based on the distance from the seismic source to the far-field point, the distance from the virtual seismic source to the far-field point, the travel time of the far-field wavelet directly below the seismic source array and the ideal wavelet. The application considers the influence of the bubble and the gun array movement in the time domain, can more accurately simulate the far-field wavelet and is more in line with the actual situation.

Description

Technical Field

[0001] This invention relates to the field of geophysical exploration technology, and in particular to a method, apparatus and equipment for simulating far-field wavelets based on near-field recordings. Background Technology

[0002] In marine seismic data processing, signal deconvolution is a fundamental and crucial step. It can suppress bubbles and virtual reflections, while simultaneously achieving zero-phase wavelet processing. Accurate wavelet information is essential for signal deconvolution, and the wavelet determines its effectiveness; therefore, calculating the wavelet is the first step.

[0003] In data processing, there are many methods for obtaining wavelets, with commonly used methods including far-field wavelet-based and seismic data-driven methods. Conventional far-field wavelets are theoretical wavelets obtained through forward modeling under the assumption of still water conditions. These wavelets differ significantly from those acquired in actual data collection, sometimes resulting in poor deconvolution performance. Seismic data-driven methods, on the other hand, extract wavelets from seismic data and achieve better results. However, in shallow water areas, various seismic waves are mixed together, making it difficult to extract an ideal wavelet. Furthermore, data-driven methods are based on multi-trace statistical approaches, making it difficult to implement trace-by-trace processing. Summary of the Invention

[0004] In view of the above problems, the present invention is proposed to provide a method, apparatus and device for simulating far-field wavelets based on near-field recording to overcome or at least partially solve the above problems.

[0005] In a first aspect, embodiments of the present invention provide a method for simulating far-field wavelets based on near-field recording, which may include:

[0006] The velocity of the near-field detector is determined based on the velocity of the seismic source ship.

[0007] The travel time at each sampling moment is determined based on the sampling interval in the time direction;

[0008] Based on the near-field record of the near-field detector, the motion velocity of the near-field detector, and the travel time at each sampling moment, the distance from the seismic source to the near-field detector and the distance from the virtual seismic source to the near-field detector are determined to construct the ideal wavelet corresponding to each sampling moment.

[0009] Based on the acquired near-field records from the near-field detector, the distance from the seismic source to the far-field point and the distance from the virtual seismic source to the far-field point are determined.

[0010] Based on the number of sampling points and the sampling interval in the time direction corresponding to the travel time, the travel time of the far-field wavelet directly below the source array is determined.

[0011] The far-field wavelet is simulated and generated based on the distance from the source to the far-field point, the distance from the virtual source to the far-field point, the travel time of the far-field wavelet directly below the source array, and the ideal wavelet.

[0012] Optionally, the method may further include:

[0013] Obtain the near-field record and time-direction sampling interval of the near-field detector.

[0014] Optionally, the distance from the seismic source to the near-field detector is determined based on the near-field record, the velocity of the near-field detector, and the travel time at each sampling moment, using the following formula:

[0015]

[0016] in, It is the serial number of the near-field detector. It's the air gun serial number. , It refers to the number of air guns; , These are the horizontal and vertical coordinates of the air gun, respectively. It's the depth of the air gun; This is the moment when earthquake data was acquired; It is the speed at which the bubbles rise, typically 1 m / s.

[0017] Optionally, the distance from the virtual source to the near-field detector is determined based on the near-field record, the velocity of the near-field detector, and the travel time at each sampling moment, using the following formula:

[0018]

[0019] in, It is the serial number of the near-field detector. It's the air gun serial number. , It is the number of air guns; , These are the horizontal and vertical coordinates of the air gun, respectively. It's the depth of the air gun; This is the moment when earthquake data was acquired; It is the speed at which the bubbles rise, typically 1 m / s.

[0020] Optionally, the ideal wavelet corresponding to each sampling time is determined by the following formula:

[0021]

[0022] in, It is the speed at which seismic waves propagate in water, typically 1500 m / s; It is the reflectance of the sea surface, typically 1.0;

[0023] and When the sampling points are not integers, spline functions or sinc functions are needed for interpolation.

[0024] Optionally, the distance from the seismic source to the far-field point is determined based on the acquired near-field record from the near-field detector using the following formula:

[0025]

[0026] in, It is the serial number of the near-field detector. It's the air gun serial number. , It is the number of air guns; , These are the horizontal and vertical coordinates of the center of the air gun array, respectively. It is the depth of the far-field point, typically 10,000 m; , These are the horizontal and vertical coordinates of the air gun, respectively. It refers to the depth of the air gun.

[0027] Optionally, the distance from the virtual source to the far-field point is determined based on the acquired near-field record from the near-field detector using the following formula:

[0028]

[0029] in, It is the serial number of the near-field detector. It's the air gun serial number. , It is the number of air guns; , These are the horizontal and vertical coordinates of the center of the air gun array, respectively. It is the depth of the far-field point, typically 10,000 m; , These are the horizontal and vertical coordinates of the air gun, respectively. It refers to the depth of the air gun.

[0030] Optionally, the far-field wavelet, simulated based on the distance from the seismic source to the far-field point, the distance from the virtual seismic source to the far-field point, the travel time of the far-field wavelet directly below the air gun array, and the ideal wavelet, is determined by the following formula:

[0031]

[0032] in, For each air gun, the ideal sub-wavelength; It is the speed at which seismic waves propagate in water, typically 1500 m / s; It is the reflectance of the sea surface, typically 1.0;

[0033] and When the sampling points are not integers, spline functions or sinc functions are needed for interpolation.

[0034] Secondly, embodiments of the present invention provide a device for simulating far-field wavelets based on near-field recording, which may include:

[0035] A motion velocity determination module is used to determine the motion velocity of the near-field detector based on the velocity of the seismic source ship;

[0036] The travel time determination module is used to determine the travel time at each sampling moment based on the time direction sampling interval;

[0037] An ideal wavelet construction module is used to determine the distance from the seismic source to the near-field detector and the distance from the virtual seismic source to the near-field detector based on the near-field record of the near-field detector, the motion velocity of the near-field detector, and the travel time at each sampling moment, so as to construct the ideal wavelet corresponding to each sampling moment;

[0038] The far-field point distance determination module is used to determine the distance from the seismic source to the far-field point and the distance from the virtual seismic source to the far-field point based on the acquired near-field records of the near-field detector.

[0039] The far-field wavelet travel time determination module is used to determine the travel time of the far-field wavelet directly below the air gun array based on the number of sampling points corresponding to the travel time and the sampling interval in the time direction.

[0040] The far-field wavelet simulation module is used to simulate the far-field wavelet based on the distance from the seismic source to the far-field point, the distance from the virtual seismic source to the far-field point, the travel time of the far-field wavelet directly below the air gun array, and the ideal wavelet.

[0041] Thirdly, embodiments of the present invention provide a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for simulating far-field wavelets based on near-field recordings as described in the first aspect.

[0042] Fourthly, embodiments of the present invention provide a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the method for simulating far-field wavelets based on near-field recordings as described in the first aspect.

[0043] The beneficial effects of the above-described technical solutions provided in the embodiments of the present invention include at least the following:

[0044] This invention provides a method, apparatus, and device for simulating far-field wavelets based on near-field recordings. The invention utilizes near-field recordings to obtain ideal wavelets, and then calculates the vertical far-field wavelets. The calculation process is performed in the time domain. Compared to frequency domain methods, this invention considers the effects of bubble and gun array motion in the time domain, enabling a more accurate simulation of far-field wavelets that better reflects reality. It can provide more precise wavelets for signal deconvolution and other processes. The primary application of simulating far-field wavelets is to provide more accurate wavelets for subsequent seismic processing steps such as signal deconvolution, resulting in better processing results.

[0045] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings.

[0046] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0047] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0048] Figure 1 This is a flowchart of the method for simulating far-field wavelets based on near-field recording provided in an embodiment of the present invention;

[0049] Figure 2 This is an example of near-field recording provided in an embodiment of the present invention;

[0050] Figure 3 The embodiments of the present invention are based on Figure 2 A definite ideal wavelet;

[0051] Figure 4 The embodiments of the present invention are based on Figure 3 Simulated far-field wavelet;

[0052] Figure 5 This is a schematic diagram of the device for simulating far-field wavelets based on near-field recording provided in an embodiment of the present invention. Detailed Implementation

[0053] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be completely conveyed to those skilled in the art.

[0054] Term Explanation:

[0055] Near-field recording: In English, it is near field hydrophone, and in oil exploration, it is generally translated as near-field recording. Since the near-field geophones are located one meter directly above each gun, these geophones are called near-field geophones (hydrophones). Here, the near field refers to being very close to the gun array, generally 1m.

[0056] Far field: Theoretically, the distance of the far field should satisfy , where f is the frequency, D is the maximum size of the gun array space, and v is the propagation speed of sound waves in water. Generally, it is required that the distance from it to the air gun array is greater than 300m.

[0057] Far-field wavelet: The wavelet measured by the far-field geophones is the far-field wavelet. If measured actually, the requirements are as follows: Select a deep water area with relatively calm sea surface and place the geophones for detecting the far-field wavelet hundreds of meters deep below the air gun array. Its depth is related to the size of the air gun array. To avoid contamination of the far-field wavelet, the distance from the geophone to the seabed needs to be reserved large enough so that the time for the seabed reflection to reach the geophone is much greater than the time for the source wavelet to reach the geophone. The method of obtaining the far-field wavelet by actual measurement has high environmental requirements, requires placing geophones at a certain depth (usually hundreds of meters underwater), has high measurement costs, and is difficult to operate. Therefore, it is not often used in actual seismic exploration. In actual seismic data processing, the often adopted methods are data-driven methods (extracted from seismic data) and methods based on near-field recording.

[0058] OBN: Ocean Bottom Node, abbreviated as the seabed node, which is a multi-component seismic acquisition method that can independently acquire and record seismic signals located on the seabed and is the fastest developing marine seismic exploration method currently.

[0059] In the embodiments of the present invention, a method for simulating far-field wavelets based on near-field recording is provided. This method uses near-field recording to simulate far-field wavelets during the processing of marine seismic data, provides wavelet information for subsequent wavelet deconvolution, multiple wave suppression, etc., and further improves the imaging quality of seismic data.

[0060] Refer to Figure 1 As shown, this method may include:

[0061] Step S11: Obtain the near-field record and time direction sampling interval of the near-field detector.

[0062] This step involves acquiring the collected data, specifically the near-field recordings. and time direction sampling interval ;

[0063] in, It is the serial number of the near-field detector. , This is the number of near-field detectors. , These are the horizontal and vertical coordinates of the near-field detector; It is the depth of the near-field detector.

[0064] Reference Figure 2 The image shows an example of a near-field record, in which the gun array consists of 18 air guns excited by seismic sources, corresponding to 18 near-field records.

[0065] Step S12: Determine the velocity of the near-field detector based on the velocity of the seismic source ship.

[0066] Determine the near-field detector in and directional speed of movement and :

[0067] (1)

[0068] (2)

[0069] in, It is the velocity of the source ship, which is obtained from field records or calculated using the distance and time between the two ships at the time of the seismic source excitation; Is the direction of the epicenter ship and The included angle of the axis.

[0070] Step S13: Determine the travel time for each sampling moment based on the time direction sampling interval.

[0071] Calculate the travel time at each sampling time. :

[0072] (3)

[0073] in, It is the sequence number of the sampling time. It is the sampling interval in the time direction.

[0074] Step S14: Based on the near-field record of the near-field detector, the motion velocity of the near-field detector, and the travel time at each sampling moment, determine the distance from the seismic source to the near-field detector and the distance from the virtual seismic source to the near-field detector, so as to construct the ideal wavelet corresponding to each sampling moment.

[0075] After the air gun is fired, it acts as a seismic source, and the excited energy propagates downwards to form seismic waves. However, some energy also propagates upwards. Since the water surface is a very good reflector, these waves are reflected by the water surface and propagate downwards again to form new seismic waves. These new seismic waves can be considered as originating from a virtual seismic source. This virtual seismic source and the air gun array (seismic source) are symmetrical about the water surface. In this embodiment of the invention, the air gun with the ideal wavelet as the seismic source is an air gun array composed of multiple air guns, and the wavelet excited by each air gun is the ideal wavelet.

[0076] On the one hand, the distance from the seismic source (air gun) to the near-field detector is determined at each sampling time. :

[0077] (4)

[0078] On the other hand, the distance from the virtual source to the near-field detector is determined at each sampling moment. :

[0079] (5)

[0080] in, It is the serial number of the near-field detector. It's the air gun serial number. , It is the number of air guns; , These are the horizontal and vertical coordinates of the air gun, respectively. It's the depth of the air gun; This is the moment when earthquake data was acquired; It is the speed at which the bubbles rise, typically 1 m / s;

[0081] Then, based on the following formula (6), the ideal wavelet corresponding to each sampling time is constructed:

[0082] (6)

[0083] in, It is the speed at which seismic waves propagate in water, typically 1500 m / s; It is the reflectance of the sea surface, typically 1.0;

[0084] and When the sampling points are non-integer, interpolation using spline functions or the sinc function is required. (See reference...) Figure 3 The image shows an example of a defined ideal wavelet.

[0085] Step S15: Based on the acquired near-field records from the near-field detector, determine the distance from the seismic source to the far-field point and the distance from the virtual seismic source to the far-field point.

[0086] In this embodiment of the invention, the air gun serving as the seismic source is an array of multiple air guns, which is generally rectangular, with the coordinates of its center being X and Y. Therefore, the distance from the seismic source to the far-field point is determined by the following formula (7):

[0087] (7)

[0088] The distance from the virtual source to the far-field point is determined by the following formula (8):

[0089] (8)

[0090] in, It's the air gun serial number. , It is the number of air guns; , These are the horizontal and vertical coordinates of the center of the air gun array, respectively. It is the depth of the far-field point, typically 10,000 m; , These are the horizontal and vertical coordinates of the air gun, respectively. It refers to the depth of the air gun.

[0091] Step S16: Based on the number of sampling points corresponding to the travel time and the sampling interval in the time direction, determine the travel time of the far-field wavelet directly below the source array.

[0092] Travel time of the far-field wavelet directly below the air gun array :

[0093] (9)

[0094] in, This is the number of sampling points corresponding to the trip. It is the sampling interval in the time direction.

[0095] Step S17: Based on the distance from the source to the far-field point, the distance from the virtual source to the far-field point, the travel time of the far-field wavelet directly below the source array, and the ideal wavelet, simulate and generate the far-field wavelet.

[0096] Determined by the following formula:

[0097]

[0098] in, For each air gun, the ideal sub-wavelength; It is the speed at which seismic waves propagate in water, typically 1500 m / s; It is the reflectance of the sea surface, typically 1.0;

[0099] and When the sampling points are not integers, spline functions or sinc functions are needed for interpolation.

[0100] Reference Figure 4 The image shows an example of a simulated far-field wavelet.

[0101] This invention utilizes near-field recordings to obtain an ideal wavelet, and then calculates the vertical far-field wavelet, with the calculation process implemented in the time domain. Compared to frequency domain methods, this invention's embodiments consider the effects of bubble and gun array motion in the time domain, enabling a more accurate simulation of the far-field wavelet and better reflecting reality. It can provide more precise wavelets for signal deconvolution and other processes. The primary application of simulating the far-field wavelet is to provide more accurate wavelets for subsequent seismic processing steps such as signal deconvolution, resulting in better processing results.

[0102] Based on the same inventive concept, this invention also provides a device for simulating far-field wavelets based on near-field recording, referring to... Figure 5 As shown, the device may include: an acquisition module 11, a motion velocity determination module 12, a travel time determination module 13, an ideal wavelet construction module 14, a far-field point distance determination module 15, a far-field wavelet travel time determination module 16, and a far-field wavelet simulation module 17. Its working principle is as follows:

[0103] The acquisition module 11 is used to acquire the near-field record and time-direction sampling interval of the near-field detector;

[0104] The motion speed determination module 12 is used to determine the motion speed of the near-field detector based on the speed of the seismic source ship.

[0105] The travel time determination module 13 is used to determine the travel time at each sampling moment based on the time direction sampling interval;

[0106] The ideal wavelet construction module 14 is used to determine the distance from the seismic source to the near-field detector and the distance from the virtual seismic source to the near-field detector based on the near-field record of the near-field detector, the motion velocity of the near-field detector, and the travel time at each sampling moment, so as to construct the ideal wavelet corresponding to each sampling moment;

[0107] The far-field point distance determination module 15 is used to determine the distance from the seismic source to the far-field point and the distance from the virtual seismic source to the far-field point based on the acquired near-field records of the near-field detector;

[0108] The far-field wavelet travel time determination module 16 is used to determine the travel time of the far-field wavelet directly below the air gun array based on the number of sampling points corresponding to the travel time and the sampling interval in the time direction.

[0109] The far-field wavelet simulation module 17 is used to simulate the far-field wavelet based on the distance from the source to the far-field point, the distance from the virtual source to the far-field point, the travel time of the far-field wavelet directly below the air gun array, and the ideal wavelet.

[0110] Optionally, the ideal wavelet construction module 14 is specifically used to: determine the distance from the seismic source to the near-field detector based on the near-field record of the near-field detector, the motion velocity of the near-field detector, and the travel time at each sampling moment, i.e., determined by the following formula:

[0111]

[0112] in, It's the air gun serial number. , It is the number of air guns; , These are the horizontal and vertical coordinates of the air gun, respectively. It's the depth of the air gun; This is the moment when earthquake data was acquired; It is the speed at which the bubbles rise, typically 1 m / s.

[0113] The ideal wavelet construction module 14 is specifically used to determine the distance from the virtual source to the near-field detector based on the near-field record of the near-field detector, the motion velocity of the near-field detector, and the travel time at each sampling moment, i.e., determined by the following formula:

[0114]

[0115] in, It is the serial number of the near-field detector. It's the air gun serial number. , It is the number of air guns; , These are the horizontal and vertical coordinates of the air gun, respectively. It's the depth of the air gun; This is the moment when earthquake data was acquired; It is the speed at which the bubbles rise, typically 1 m / s.

[0116] Ideal wavelet construction module 14 is specifically used to: construct the ideal wavelet corresponding to each sampling time, that is, to determine it through the following formula:

[0117]

[0118] in, It is the speed at which seismic waves propagate in water, typically 1500 m / s; It is the reflectance of the sea surface, typically 1.0;

[0119] and When the sampling points are not integers, spline functions or sinc functions are needed for interpolation.

[0120] The far-field point distance determination module 15 is specifically used to determine the distance from the seismic source to the far-field point based on the acquired near-field record of the near-field detector, using the following formula:

[0121]

[0122] in, It's the air gun serial number. , It is the number of air guns; , These are the horizontal and vertical coordinates of the center of the air gun array, respectively. It is the depth of the far-field point, typically 10,000 m; , These are the horizontal and vertical coordinates of the air gun, respectively. It refers to the depth of the air gun.

[0123] The far-field point distance determination module 15 is specifically used to determine the distance from the virtual source to the far-field point based on the acquired near-field record of the near-field detector, using the following formula:

[0124]

[0125] in, It's the air gun serial number. , It is the number of air guns; , These are the horizontal and vertical coordinates of the center of the air gun array, respectively. It is the depth of the far-field point, typically 10,000 m; , These are the horizontal and vertical coordinates of the air gun, respectively. It refers to the depth of the air gun.

[0126] The far-field wavelet simulation module 17 is specifically used to simulate the far-field wavelet based on the distance from the seismic source to the far-field point, the distance from the virtual seismic source to the far-field point, the travel time of the far-field wavelet directly below the air gun array, and the ideal wavelet, i.e., determined by the following formula:

[0127]

[0128] in, For each air gun, the ideal sub-wavelength; It is the speed at which seismic waves propagate in water, typically 1500 m / s; It is the reflectance of the sea surface, typically 1.0;

[0129] and When the sampling points are not integers, spline functions or sinc functions are needed for interpolation.

[0130] Based on the same inventive concept, this embodiment of the invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method for simulating far-field wavelets based on near-field recording.

[0131] Based on the same inventive concept, this embodiment of the invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the above-described method for simulating far-field wavelets based on near-field recording.

[0132] The principles by which the above-described apparatus, client, medium, related equipment, and system in this embodiment solve the problem are similar to those of the aforementioned method. Therefore, their implementation can refer to the implementation of the aforementioned method, and repeated details will not be repeated.

[0133] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0134] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0135] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0136] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0137] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for simulating far-field wavelets based on near-field recording, characterized in that, include: Based on the speed of the seismic source ship, determine the velocity of the near-field detector; The travel time at each sampling moment is determined based on the sampling interval in the time direction; Based on the near-field record of the near-field detector, the motion velocity of the near-field detector, and the travel time at each sampling moment, the distance from the seismic source to the near-field detector and the distance from the virtual seismic source to the near-field detector are determined to construct the ideal wavelet corresponding to each sampling moment. Based on the acquired near-field records from the near-field detector, the distance from the seismic source to the far-field point and the distance from the virtual seismic source to the far-field point are determined. Based on the number of sampling points and the sampling interval in the time direction corresponding to the travel time, the travel time of the far-field wavelet directly below the source array is determined. The far-field wavelet is simulated and generated based on the distance from the source to the far-field point, the distance from the virtual source to the far-field point, the travel time of the far-field wavelet directly below the source array, and the ideal wavelet. The distance from the seismic source to the near-field detector is determined by the near-field record based on the near-field detector, the velocity of the near-field detector, and the travel time at each sampling moment, using the following formula: ； in, It is the serial number of the near-field detector; It's the air gun serial number. , It refers to the number of air guns; , These are the horizontal and vertical coordinates of the near-field detector; It is the depth of the near-field detector; and The velocity of the near-field detector in the x and y directions; , These are the horizontal and vertical coordinates of the air gun, respectively. It's the depth of the air gun; This is the moment when earthquake data was acquired; It is the speed at which the bubble rises, which is 1 m / s.

2. The method according to claim 1, characterized in that, Also includes: Obtain the near-field record and time-direction sampling interval of the near-field detector.

3. The method according to claim 1, characterized in that, The distance from the virtual seismic source to the near-field detector is determined by the near-field record based on the near-field detector, the velocity of the near-field detector, and the travel time at each sampling moment, using the following formula: ； in, It is the serial number of the near-field detector. It's the air gun serial number. , It refers to the number of air guns; , These are the horizontal and vertical coordinates of the near-field detector; It is the depth of the near-field detector; and The velocity of the near-field detector in the x and y directions; , These are the horizontal and vertical coordinates of the air gun, respectively. It's the depth of the air gun; This is the moment when earthquake data was acquired; It is the speed at which the bubble rises, which is 1 m / s.

4. The method according to claim 3, characterized in that, The ideal wavelet corresponding to each sampling time is determined by the following formula: ； in, It is the ideal sub-wave of each air gun; It is the speed at which seismic waves travel in water, which is 1500 m / s; It is the reflectance of the sea surface, which is 1.0; and When the sampling points are not integers, spline functions or sinc functions are needed for interpolation.

5. The method according to claim 1, characterized in that, The distance from the seismic source to the far-field point is determined based on the acquired near-field record from the near-field detector using the following formula: ； in, It's the air gun serial number. , It refers to the number of air guns; , These are the horizontal and vertical coordinates of the center of the air gun array, respectively. It is the depth of the far-field point, which is 10,000m; , These are the horizontal and vertical coordinates of the air gun, respectively. It refers to the depth of the air gun.

6. The method according to claim 5, characterized in that, Based on the acquired near-field records from the near-field detector, the distance from the virtual source to the far-field point is determined using the following formula: ； in, It's the air gun serial number. , It refers to the number of air guns; , These are the horizontal and vertical coordinates of the center of the air gun array, respectively. It is the depth of the far-field point, which is 10,000m; , These are the horizontal and vertical coordinates of the air gun, respectively. It refers to the depth of the air gun.

7. The method according to claim 6, characterized in that, The far-field wavelet is simulated and generated based on the distance from the seismic source to the far-field point, the distance from the virtual seismic source to the far-field point, the travel time of the far-field wavelet directly below the seismic source array, and the ideal wavelet, and is determined by the following formula: ； in, For each air gun, the ideal sub-wavelength; The travel time of the far-field sub-wavelength directly below the air gun array; It is the speed at which seismic waves travel in water, which is 1500 m / s; It is the reflectance of the sea surface, which is 1.0; and When the sampling points are not integers, spline functions or sinc functions are needed for interpolation.

8. A device for simulating far-field wavelets based on near-field recording, characterized in that, include: The motion velocity determination module is used to determine the motion velocity of the near-field detector based on the velocity of the seismic source ship. The travel time determination module is used to determine the travel time at each sampling moment based on the sampling interval in the time direction; An ideal wavelet construction module is used to determine the distance from the seismic source to the near-field detector and the distance from the virtual seismic source to the near-field detector based on the near-field record of the near-field detector, the motion velocity of the near-field detector, and the travel time at each sampling moment, so as to construct the ideal wavelet corresponding to each sampling moment; The far-field point distance determination module is used to determine the distance from the seismic source to the far-field point and the distance from the virtual seismic source to the far-field point based on the acquired near-field records of the near-field detector. The far-field wavelet travel time determination module is used to determine the travel time of the far-field wavelet directly below the source array based on the number of sampling points corresponding to the travel time and the sampling interval in the time direction. The far-field wavelet simulation module is used to simulate and generate the far-field wavelet based on the distance from the source to the far-field point, the distance from the virtual source to the far-field point, the travel time of the far-field wavelet directly below the source array, and the ideal wavelet. The distance from the seismic source to the near-field detector is determined by the near-field record based on the near-field detector, the velocity of the near-field detector, and the travel time at each sampling moment, using the following formula: ； in, It is the serial number of the near-field detector; It's the air gun serial number. , It refers to the number of air guns; , These are the horizontal and vertical coordinates of the near-field detector; It is the depth of the near-field detector; and The velocity of the near-field detector in the x and y directions; , These are the horizontal and vertical coordinates of the air gun, respectively. It's the depth of the air gun; This is the moment when earthquake data was acquired; It is the speed at which the bubble rises, which is 1 m / s.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by the processor, the program implements the method for simulating far-field wavelets based on near-field recordings as described in any one of claims 1 to 7.

10. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the method for simulating far-field wavelets based on near-field recordings as described in any one of claims 1 to 7.

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